1. Field of the Invention
The invention relates to an electro-magnetically actuated valve arrangement for flowing media comprising a sleeve in which an intake and a discharge valve each having a valve seat is applied, a permanent magnet arranged axially displaceable being provided therebetween, the flow of the medium from the intake to the discharge valve being controllable via said permanent magnet.
2. Description of the Prior Art
Given valve arrangements of this type, the permanent magnet works with a high frequency so that the valves can be closed or opened in the shortest possible time. When an air gap is provided between the permanent magnet and the sleeve for the passage of the medium, it can occur that the permanent magnet ends up in an oblique position and is thereby seized in the sleeve. German AS No. 1 232 424 discloses a valve arrangement of the type described above wherein the problem is resolved in that a radially magnetized cylindrical magnet is employed as permanent magnet and a sleeve of magnetizable metal is employed. The manufacture of such a permanent magnet is complicated and costly.
U.S. Pat. No. 4,240,468 discloses a further electromagnetically actuated valve arrangement comprising a cylindrical armature of iron which controls the flow of a gas between two valves. The armature whose outside wall slides against the inside wall of a sleeve-like iron member comprises a plurality of longitudinal grooves and an axial bore for the passage of the gas in the circumferential surface thereof. For the discharge of the gas, either concentrically arranged flow bores or a concentrically proceeding annular gap which are not congruent with the longitudinal grooves or with the axial bore of the armature discharge into the discharge valve. Due to the multitude of grooves and bores in the armature or valve, the manufacture of this valve arrangement is relatively involved.